Fuel cells with new old twist
University of Pennsylvania engineers have developed a prototype fuel cell that runs on diesel, a readily available liquid fuel source.
Philadelphia—In a move that brings fuel cells closer to becoming viable, chemical engineers at the University of Pennsylvania developed a prototype fuel cell that runs on a readily available liquid fuel source: diesel.
Scientists, corporations, and the military are all interested in fuel cells, which are far more efficient and less polluting than other energy sources. Work to develop commercial fuel cells, however, has been hindered by the limited fuel sources on which they have been known to run.
“There used to be a saying that you could run a fuel cell on any fuel as long as it’s hydrogen,” said Raymond J. Gorte, professor of chemical engineering at Penn.
“In our earlier work, we were unable to feed liquid diesel to the fuel cell because we did not have a means for vaporizing fuels that have a low vapor pressure at room temperature,” Gorte said, adding they can now feed the liquids to a fuel cell using a method analogous to a fuel injector.
The Penn fuel cell runs directly on hydrocarbons, without requiring complicated reforming into hydrogen either within the device or at specialized filling stations. Generating electric power through controlled electrochemical reactions rather than combustion, its only emissions are water, carbon dioxide, and heat.
Smaller than a penny, the prototype fuel cell operates in a furnace set at 700°C. A commercial, self-contained fuel cell would ideally generate that heat itself using the fuel placed in it.
Although unlikely to replace household batteries for small appliances and portable electronics, researchers have suggested fuel cells might be appropriate for powering cars and laptop computers.
Fuel cells could also make possible electric generators that operate on propane or butane. Gorte’s team is interested in developing a relatively small, 5-kilowatt fuel cell. Such a unit, placed in a home’s basement, could generate electricity from natural gas, using the excess energy to heat a home or its hot water.
“It’s much more efficient to produce energy on-site than it is to make it many miles away,” Gorte said.